Referencing other forms

[Christopher Weaver]

This is a broad question. I am developing a multiform Windows applications.
There is only one database involved. I would like to establish one
connection object and a few DataAdapters and DataSets that I can use in
several of the windows. How and where do I instantiate these objects so I
can utilize them from any of the forms in the application?

Thanks.

 

[Nicholas Paldino [.NET/C# MVP]]

Christopher,

I would create a base form that instantiates this stuff for you, and
then derive from that form for all of your forms.

Also, you should not create one database connection (which might mean
you keep it open most of the time). If anything, have a factory method that
creates connections for you, which you then open and close as soon as you
are done.

Hope this helps.

 

[Chad Z. Hower aka Kudzu]

I would create a base form that instantiates this stuff for you,
and
then derive from that form for all of your forms.

I think he wants to share the instance data though, which this wont allow.



--
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"Programming is an art form that fights back"

Make your ASP.NET applications run faster
http://www.atozed.com/IntraWeb/

 

[Nicholas Paldino [.NET/C# MVP]]

He could store/return it in a set of static fields/properties/methods on
the base class, which would allow for that.

 

[Chad Z. Hower aka Kudzu]

He could store/return it in a set of static
fields/properties/methods on
the base class, which would allow for that.

Yes, but then he wont be able to bind at design time AFAIK.


--
Chad Z. Hower (a.k.a. Kudzu) - http://www.hower.org/Kudzu/
"Programming is an art form that fights back"

Develop ASP.NET applications easier and in less time:
http://www.atozed.com/IntraWeb/

 

[Mark Rae]

Christopher,

This is a broad question. I am developing a multiform Windows
applications. There is only one database involved. I would like to
establish one connection object and a few DataAdapters and DataSets that I
can use in several of the windows. How and where do I instantiate these
objects so I can utilize them from any of the forms in the application?

I would advise against this because you will almost certainly be holding
your connection open for as long as your app is open. This is OK when you're
the only user accessing your database, but not so good when there are more
than even a few concurrent users.

Instead, I would recommend a Data Access Layer, often known as a DAL.
This should get you started:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnpag2/html/daab.asp

Mark

 

[Christopher Weaver]

Perhaps I'm expecting this to be altogether more visual in nature than it
is.

I thought that if I created form A and form B then put a bunch of code in
module C.cs that somehow I could get A and B to call the functions in C.cs
in such a manner that the code in C.cs could affect the properties of A and
B.

If I understand you correctly, I should start with frmSuperClass then
descend frmA and frmB from it so that I could put any code that I wanted to
affect frmA and frmB in frmSuperClass.

Regarding the connection. I open it when needed and close it when I'm
finished. It's just that I didn't want to use any additional resouces for
another connection object and I didn't want to add another layer of
complexity to the app. If I follow your reasoning, you would build a
function that would return a connection when called. Where would you put
such a function? Would this require that all forms that need to access data
be descended from a common form with the connection factory function within
it? What about the connection used by Crystal Reports?

Thanks.

Christopher,

I would create a base form that instantiates this stuff for you, and
then derive from that form for all of your forms.

Also, you should not create one database connection (which might mean
you keep it open most of the time). If anything, have a factory method
that creates connections for you, which you then open and close as soon as
you are done.

Hope this helps.


--
- Nicholas Paldino [.NET/C# MVP]
- (e-mail address removed)

This is a broad question. I am developing a multiform Windows
applications. There is only one database involved. I would like to
establish one connection object and a few DataAdapters and DataSets that
I can use in several of the windows. How and where do I instantiate
these objects so I can utilize them from any of the forms in the
application?

Thanks.